Stackable marker



FIG. 1 is a perspective view of an oval-shaped, stackable marker in accordance with the first embodiment of the invention;

FIG. 2 is a front elevational view of a second embodiment of my design of FIG. 1, the rear view being identical thereto;

FIG. 3 is a side elevational view of FIG. 2, the opposite side being identical thereto;

FIG. 4 is a top plan view of FIG. 2;

FIG. 5 is a front elevational view of a third embodiment of my design of FIG. 1, the rear view being identical thereto;

FIG. 6 is a side elevational view of FIG. 5, the opposite side being identical thereto;

FIG. 7 is a top plan view of FIG. 5;

FIG. 8 is a front elevational view of a fourth embodiment of my design of FIG. 1, the rear view being identical thereto;

FIG. 9 is a side elevational view of FIG. 8, the opposite side being identical thereto;

FIG. 10 is a top plan view of FIG. 8; and,

FIG. 11 is a bottom plan view of FIGS. 1, 2, 5, and 8. 

The ornamental design for a stackable marker, as shown and described. 